public class LongArrayFIFOQueue extends AbstractLongPriorityQueue implements java.io.Serializable
Instances of this class represent a FIFO queue using a backing
array in a circular way. The array is enlarged and shrunk as needed. You can use the trim()
method
to reduce its memory usage, if necessary.
This class provides additional methods that implement a deque (double-ended queue).
Modifier and Type | Field and Description |
---|---|
static int |
INITIAL_CAPACITY
The standard initial capacity of a queue.
|
Constructor and Description |
---|
LongArrayFIFOQueue()
Creates a new empty queue with standard initial capacity.
|
LongArrayFIFOQueue(int capacity)
Creates a new empty queue with given capacity.
|
Modifier and Type | Method and Description |
---|---|
void |
clear()
Removes all elements from this queue.
|
LongComparator |
comparator()
Returns
null (FIFO queues have no comparator). |
long |
dequeueLastLong()
Dequeues the last element from the queue.
|
long |
dequeueLong()
Dequeues the first element from the queue.
|
void |
enqueue(long x)
Enqueues a new element.
|
void |
enqueueFirst(long x)
Enqueues a new element as the first element (in dequeuing order) of the queue.
|
long |
firstLong()
Returns the first element of the queue.
|
long |
lastLong()
Returns the last element of the queue.
|
int |
size()
Returns the number of elements in this queue.
|
void |
trim()
Trims the queue to the smallest possible size.
|
dequeue, enqueue, first, last
changed, isEmpty
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
changed, isEmpty
public static final int INITIAL_CAPACITY
public LongArrayFIFOQueue(int capacity)
capacity
- the initial capacity of this queue.public LongArrayFIFOQueue()
public LongComparator comparator()
null
(FIFO queues have no comparator).comparator
in interface LongPriorityQueue
comparator
in interface PriorityQueue<java.lang.Long>
null
.PriorityQueue.comparator()
public long dequeueLong()
dequeueLong
in interface LongPriorityQueue
java.util.NoSuchElementException
- if the queue is empty.public long dequeueLastLong()
java.util.NoSuchElementException
- if the queue is empty.public void enqueue(long x)
LongPriorityQueue
enqueue
in interface LongPriorityQueue
x
- the element to enqueue.public void enqueueFirst(long x)
public long firstLong()
firstLong
in interface LongPriorityQueue
java.util.NoSuchElementException
- if the queue is empty.public long lastLong()
lastLong
in interface LongPriorityQueue
lastLong
in class AbstractLongPriorityQueue
java.util.NoSuchElementException
- if the queue is empty.public void clear()
PriorityQueue
clear
in interface PriorityQueue<java.lang.Long>
public void trim()
public int size()
PriorityQueue
size
in interface PriorityQueue<java.lang.Long>